Attachable indicator for fuses



' Nov. 10,1925- J. B. GLOWACKI ATTACHABLE INDICATOR FOR FUSES Filed March 9, 1922 Patented Nov. 10, 1925.

PATENT OFFICE.

JOHN B. GLOWACKI, OF CHICAGO, ILLINOIS.

ATTACHABLE INDICATOR FOR FUSES.

Application filed March 9, 1922. Serial No. 542,254.

To all whom it may concern:

Be it known that I, J OHN B. GLowAcKI, a citizen of the Republic of Poland, having declared my intention of becoming a'citizen of the United States, and a resident of the city of Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Attachable Indicators for Fuses; and I do hereby declare that the following is a full, clear, and exact description of the same, reference being had to the accompanying drawings, and to the numerals of reference marked thereon, which form a part of this specification.

It is an object of this invention to provide an indicating device of the type in which a cap over the outlet of a fuse is to be disrupted or displaced when the fuse is blown which shall have provision for cooling and extinguishing flame even after the cap is removed.

It is a further object of this invention to provide a fuse with an indicating device which, by permitting a slow emission of smoke, will enable the blown fuse to be readily identified.

It is a further object of this invention to provide a fuse with a plurality of outlets at -difi'erent levels so that a current of smoke shall emerge at one of these outlets when the fuse is blown.

Other and further important objects of this invention will be apparent from the disclosures in the drawings and specification.

The invention (in a preferred form) is illustrated on the drawings and hereinafter more fully described.

On the drawings:

Figure 1 is a side view of a fuse provided with indicators according to my invention.

Figure 2 is a section upon the line Q2 of Figure 1.

Figure 8 is an end view.

Figure 4 is a section upon the line f; of Figure 2.

As shown on the drawings:

The fuse shown is of the familiar cartridge form or may be of the plug type or any other enclosed fuse type, and is enclosed in a cylinder 1 having ferrules 1. If desired, this cylinder may be of a type having outlets at its ends as indicated at 2 in Figure 3. For indicating purposes, additional outlets are provided to the cylinder, each of which is covered by a cap 3. As shown in Figures 1 and 2, the top of the cap is provided with a perforation 4. Preferably, these caps are of gelatine or other transparent material and are cylindrical in form having their ends closed by a dome-shaped surface 5 in the middle of which is the perforation 4.

These gelatine cylinders slip down over a cylindrical boss 6 provided near its bottom with a flange 7. The bosses 6 are made of any suitable material. As illustrated in the drawings, they are made of fibre or other insulation and they are threaded at the bottom as shown at 8 to co-operate with a threaded hole in the cylinder. A tubular passage 9 extends through each of these bosses and the upper end of this passage is closed by the wall 10 at the top of the boss. A number of holes 11 in the illustrated form are made in the wall of the boss 6 a little way below the top 10 as indicated at 11. Just below the opening of the holes 11, the diameter of the boss 6 is diminished to form a shoulder 12. The part of the boss 6 below this shoulder fits closely the cylindrical gelatine cap 3 and the lower end of the gelatine cylinder is stopped by the flange 7. If when the gelatine cap is put on the boss it is wet, the cap will adhere to the boss with the result that it will be less easily displaced.

In the use of the device, it is connected in an electric circuit in the usual way and is 50 positioned that one of the two openings f is higher than the other. lVhen too great a current flows in the circuit, the fussible element contained in the cartridge is melted and perhaps vaporized. There may even be some flame formed. The products of this action escape through the passage 9 and their velocity is checked by their hit ting against the top 10 of the cylinder (i. They emerge therefore through the holes 11 at a somewhat diminished velocity. Here they impinge against the inside of the gelatine cap 8.

If the violence of the action is sufficient the pressure developed may blow the gelatine cap off of the boss. If this does not occur it is practically certain the cap will be discolored so that it will by its changed color show the observer that the fuse has been blown. If the gelatine cap sticks to the cylinder 6 strongly enough to prevent the displacement of the cap 3 even when the fuse is blown with some violence. the products of the action may disrupt the can.

If the fuse is blown by a current which is only slightly in excess of the current the circuit is intended to carry, instead of an explosive action the smoke from thefusewill. emerge slowly and the cap will be filled with smoke. The smoke will come slowly out through the perforation i so that a line steady stream of smoke will serve as an additional indication by which the observer may easily identify the blown fuse. As

such a stream of smoke persists for some minutes after the action of the fuse, the observer has time to get to the fuse and see the smoke even if the fuse is in the cellar and the. sudden cessation of current is noticed in the upper part of the house. hen the failure of lights or other circumstance indicating that a fuse is blown calls the operator to the fuse box, he thereforewill find smoke emerging from one of the fuses andso be ableto ascertain quickly. which fuse must be replaced.

Since ordinarily this smoke is heavier than air, it will flow under the influence of gravity and emerge from the lower one of the holes 4, being displaced by air which enters through the upper one of theseholes. Air may also enter through the openings 2 and pass into the interior of the cartridge through the opening 13. If either of the openings l are below the level of the openings 2, this will cause smoke to emerge from the lower oneof the openings i even if the upper opening 4 were choked or even if only one cylinder 3 with its opening d were used. If only one cylinder 3 were used and it were above the openings 2, the flow would, be in the reverse direction and smoke would emerge through theopenings 2.

The tortuous character of the passage through the holes 11 is sufficient to prevent flame from finding its way to the outside of the fuse cartridge even in the case of a sudden and violent blowing of the fuse. Danger of fire from-the fuse ignitingdts surroundings is therefore reduced to aminimum.

If the blowingof the fuse was so sudden andso violent that the cap 3is1displaced or shattered, the missin capywouldlikewise .ing. of .thefuse, an indication is serve as a tell-tale to enable'the operator to quickly locate the fuse needing attention.

Thus either with a violent or gentle blowft'orded. i am aware that numerous dedails of construction may be Varied through a wide range without departing from the principles of this invention, and I therefore do not purpose limiting the patent granted otherwise than necessitated by the prior art.

I claim as my invention:

1. Alfuse cartridge, a cylindrical tubular boss thereon, a tubular member seated on said boss, a dome-shaped closure at the end of said tubular member andhaving-aperforation therein, a flange on said boss against which said tubular member abuts, anda shoulder on said boss, the portion of said boss atone side of saidshould'er contacting with said tubular member and the portion of said boss on theother side of saidshould'er being spaced away from said tubular mem= her, said bossjhaving openings into the in teriorof said'tubu'lar member and into the interior ofsaid cartridge.

2. In an enclosed fuse construction, an outlet tube therein, saidtube having pas? sages th'rough'its wallsat an angle to the axis of the tube, and an indicator at the end of said tube surrounding the opening of said passages.

3. In an enclosed fuseconstruction, a boss, and a gelatine cap on said boss having radial orifices communicating with the interior of the fuse.

4. In an enclosed fuse construction, a boss, and agelatine capon said boss, said cap fit= ting. closely along apart of the length of said boss part of the boss within thecapbeing of a reduced diameter.

5. In an enclosed fuse construction, aboss, a gelatine cap on said boss, and a flange on said boss againstwhich said cap abuts, a portionof said boss adjacent'said flange closely fitting said capand adapted to ad'- here thereto the 'balanceof the boss within said cap being. of a redueeddiameteu In testimony whereof I have 1 hereunto subscribed my name.

' JOHN B. GLOIVACKI'. 

